1. Field of the Invention
The present invention relates to a sensing device and, more particularly, to a wallmount dual beam sensing device with a passive infrared detector and a microwave detection module.
2. Description of the Related Art
Owing to environmental awareness about energy conservation and carbon reduction, automatically controlling lighting and/or air conditioning within a specific region of a public space or a home space according to an instant environmental condition becomes an important development trend of intelligent power management. To most spaces, lighting and air conditioning are undoubtedly atop a list of energy consumption, making them easy sources of energy waste in the spaces, especially in public spaces because most people in public spaces will not turn off the unnecessary lighting and/or air conditioning when leaving. Therefore, enormous energy waste arises. To cope with the energy waste, sensing devices with infrared detectors are developed to assist energy management in public spaces, such that lighting and air conditioning can be automatically turned on or off according to environmental conditions and setting conditions for the purpose of energy conservation and carbon reduction.
However, conventional infrared detectors tend to be mounted on ceilings and appearing outside, rendering them not only aesthetically unpleasant but feasible for two-dimensional detection only. The two-dimensional detection functionality can detect the presence of people in a sensed space while failing to determine the distance between a moving object and a sensing device. Other shortcomings of infrared detection include unreliable detection result and failure in wall penetration. When infrared detection is applied to a place with multiple partitions, such as a toilet, people inside the partitions oftentimes fail to be detected and errors in detection are caused.
In contrast to infrared sensing device, ultrasonic sensing devices need to have holes formed therethrough and are thus aesthetically unpleasant. Malfunction of the ultrasonic devices can also arise from foreign matter stuffed in the holes.